Patients having a planned open surgery of thoracoabdominal aortic aneurysms and enrolled in the study will be randomized the day of the surgery in 2 groups:

• Arm 1 : Patients with aortic clamping with pre-conditioning
• Arm 2 : Patients with aortic clamping without pre-conditioning Patients will be then followed, during 60 days after surgery.

Inclusion Criteria:

1. Patient > 18 and <85 years old
2. Patient having a planned surgery for a thoracoabdominal aortic aneurysm by direct approach,
3. Patient with aortic aneurysm requiring supra-visceral aortic clamping and visceral artery reconstruction,
4. Aortic aneurysmal patient with or without distal femoral circulatory assistance,
5. Patient with aortic aneurysm of atheromatous or dissecting etiology,
6. Woman of childbearing potential with effective contraception (estrogen-progestin or intrauterine device or tubal ligation), postmenopausal woman (≥ 12 months of amenorrhea not induced by therapy)
7. Patient who read and understood the newsletter and signed the consent form
8. Patient affiliated with a social security scheme

Exclusion Criteria:

1. Patient with aortic aneurysms requiring supra-visceral aortic clamping but not requiring visceral artery reconstruction (supra-visceral aortic clamping for renal aortic juxtaposition aorta),
2. Patient with thoraco abdominal aortic aneurysms requiring a circulatory arrest (aortic aneurysms affecting the descending thoracic aorta or the aortic arch)
3. Patient requiring emergency aortic surgery
4. Patient under treatment known as interfering with PCI (Nicorandil or oral antidiabetic agents),
5. Pregnant or lactating woman (negative result of baseline blood test)
6. Participation in another interventional study within 28 days before randomization or during this study
7. Person deprived of liberty by an administrative or judicial decision or person subject to a legal measure for the protection of adults,
8. Patient under the protection of justice, patient under guardianship or curatorship.